Personal computers have become increasingly necessary in today's high technological society. These systems can usually be defined as desk top, floor standing, or portable unit that consists of a system unit having a single system processor, a display monitor, a keyboard, one or more diskette drives, a fixed disk, and an optional printer. The centerpiece of the computer system is the printed circuit board which holds and connects the system processor and its support circuitry. This printed circuit board is usually referred to as the planar. A typical planar is made from a flat sheet of glass-epoxy with the actual circuitry etched from two or more layers of conductive copper that form traces which carry the electrical signals between the electronic components fastened to the planar. Installed on the planar are a number of expansion slots which are pathways that permit electrical signals to connect with the system processor. A typical planar will accept a number of different circuitry components, such as adapter boards, I/0 boards or memories, which are plugged into the expansion slots affixed to the planar. Normally the expansion slot is in the form of a female connector with the circuitry component normally having a corresponding male-edge connector. During the installation of these circuitry components, insertion force is required to insert the edge connectors of the boards into the corresponding female connector on the planar. This force will vary depending on the number of physical contacts on the edge connector and the alignment of the connectors, and the tolerance conditions.
During insertion, forces may be generated by a user on the planar assembly which can cause the planar to flex. When this happens, not only does the planar flex but the traces comprised of the numerous electrical leads and paths running from the connectors to the processor and other components on the planar are flexed. If the traces are flexed enough severe deterioration of the traces results. In fact, enough force can be applied to the planar to cause the traces to break. As is evident, the loss of a trace on the planar can result in failure in the operation of the personal computer system.
One way of preventing the flexing of the planar is to provide a plurality of supports between the planar and the housing. In the past, these supports usually take the form of a nut and bolt with insulating washers, which are inserted between the planar and the computer housing. In some cases the fastener is comprised of plastic or other insulating material to provide an electrical isolation between the planar and the housing. These supports, while providing some relief from the flexing problems, have not totally solved the problem since they only provide support at one particular point in the planar. As can be expected, even if these supports are situated close to an extension slot, the board can still flex in between the supports causing damage to the traces. Also it is important to point out that increasing the number of these supports is undesirable because it decreases the real estate on the planar and increases cost due to the additional hardware and time of assembly.